Patrick Ball discusses how data about mass violence can seem to offer insights into patterns: is violence getting better, or worse, over time? Is violence directed more against men or women? However, in human rights data collection, we (usually) don’t know what we don’t know — and worse, what we don’t know may be systematically different from what we do know.

This talk will explore the assumption that nearly every project using data must make: that the data are representative of reality in the world. We will explore how, contrary to the standard assumption, statistical patterns in raw data tend to be quite different than patterns in the world. Statistical patterns in data reflect how the data was collected rather than changes in the real-world phenomena data purport to represent.

Using analysis of killings in Iraq, homicides committed by police in the US, killings in the conflict in Syria, and homicides in Colombia, we will contrast patterns in raw data with data in estimated total patterns of violence. The talk will show how biases in raw data can be corrected through estimation, and explain why it matters in these countries, and more generally.

Recorded on 3/24/2016.